Evaluation of the Coris Legionella V-Test. In comparison with the Trinity Biotech EIA Legionella Urinary Antigen test

Transcription

1 Evaluation of the Coris Legionella V-Test In comparison with the Trinity Biotech EIA Legionella Urinary Antigen test 06/September/2010 Coris BioConcept

2 Report of Clinical Performance Study of Legionella V-Test Coris BioConcept test in comparison with EIA Legionella Urinary Antigen test Trinity Biotech Truthful and Accurate Statement I, Jose Domínguez certify that, in my capacity as Senior Researcher, I believe to the best of my knowledge, that all data and information submitted in the above referenced Report of Clinical Performance Study are truthful and accurate and that no material fact has been omitted. These data belong to Coris BioConcept, therefore they can be used for any commercial purpose. Signature: Date: 06/ September/ 2010

3 Report of Clinical Performance Study of Legionella V-Test Coris BioConcept test in comparison with EIA Legionella Urinary Antigen test Trinity Biotech Place where test was performed: Servei de Microbiologia. Hospital Universitari Germans Trias I Pujol. Carretera del Canyet s/n Badalona. Barcelona. Spain Lead Investigator, Responsible Person of the investigation: Jose Domínguez Collaborator Investigator: Silvia Blanco Period of Testing: Two months after receiving the kits. Product evaluated: Legionella V-Test Coris BioConcept test Batch Number of kit: 2149H1006 Batch Number of sticks: 1W15G1013D Batch Number of extraction: - Comparator(s) Method(s): EIA Legionella Urinary Antigen test Trinity Biotech Batch Number of kit: - Brief description of that reference method used: The Bartels EIA assay (Bartels EIA Legionella Urinary Antigen. Bartels Inc., A Trinity Biotech Company, Wicklow, Ireland) is a direct sandwich test that uses polyclonal rabbit antibodies which react with L. pneumophila serogroup 1 antigen as the capture and detection antibody. Results were read using a microplate reader, although a visual interpretation was possible. Samples were considered positive when ratios were higher than 4 (the absorbance value was 4 times the absorbance value of the negative control). The test was performed following the manufacturer s instructions. Study Objective: The aim of this retrospective study was to evaluate the sensitivity and specificity of Legionella V-Test Coris BioConcept test in the diagnosis of Legionella pneumonia using non concentrated urine (), comparing the results to EIA Legionella Urinary Antigen test Trinity Biotech using concentrated urine (CU). Sample type tested and collection method: The test was performed using. The collected samples were stored at -80ºC.

4 Study Population and samples collected (number of samplings to test): Group 1.- Urine samples from 57 patients with pneumonia due to L. pneumophila will be studied. Legionnaires disease was diagnosed by isolation of L. pneumophila, by seroconversion, and/or by detection of soluble antigen in concentrated urine samples. Group 2.- Urine samples from 43 patients with confirmed pneumonia of other etiologies and patients with no clinical or radiological signs of pneumonia: healthy people, patients with bacteremia from a nonrespiratory focus, and patients with urinary tract infections. Methods employed: - EIA Legionella Urinary Antigen test Trinity Biotech - Legionella V-Test Coris BioConcept test - Amicon Ultra-4. Millipore Corporation. Bedford, MA Recommendations of the both manufacturers have been followed. Trials findings summary: Clinical Status POS NEG total Coris Test POS Non Concentrated Urine NEG total Sensitivity: 80.7% (TP/ (TP+FN)) Specificity: 100% (TN/ (TN+FP)) Reliability: 89% (TN+TP)/Total) Positive Predictive Value: Not applicable % (TP/(TP+FP)) Negative Predictive Value: Not applicable % (TN/ (TN+ FN)) The 11 urine samples with discordant result between CU EIA Bartels and ICT Coris results were retested by ICT Coris using CU. The antigen present in the 11 samples was concentrated 25 times by selective ultrafiltration. After concentration the ICT Coris was positive in 9 of the 11 samples (81.8%). Therefore, we could consider that the overall ICT Coris sensitivity was 96.5% (46+9/57). Interestingly, the 2 negative CU ICT Coris samples were also negative by the ICT Binax (Table 3). On the other hand, from the 11 urine samples with discordant result in 10 cases urine was available to test by the EIA Bartels using. The EIA Bartels was positive in 7 cases and negative in 3, being in the 3 cases the ICT Binax in and CU also negative (Table 3). A summary of the Study results are presented in the following figure.

5 Positive EIA Bartels CU n= 57 Positive ICT CORIS n= 46 Negative ICT CORIS n= 11 Positive ICT CORIS CU n= 9 Negative ICT CORIS CU n= 2 Negative ICT Binax n= 2 Positive EIA Bartels n= 7 Negative EIA Bartels n= 3 Urine sample not available n= 1 Negative ICT Binax & CU n= 3

6 Conclusion: 1. ICT Coris is a technique simple to perform, with good sensitivity and specificity, and the results are obtained in 15 minutes or less. 2. It s a good screening test to detect L. pneumophila antigen from urine samples. 3. Our results show that ICT Coris is comparable in sensitivity and specificity with the EIA Bartels. However, ITC Coris sensitivity is slightly lower than EIA Bartels in both non concentrated urine and concentrated urine samples. 4. The ICT Coris sensitivity increases using concentrated urine samples by selective ultrafiltration. 5. The technique is especially useful for small hospital laboratories without appropriate equipment and/or a small number of samples to perform the EIA Bartels test.

7 Table 1. Results for Each Specimen from patients Group 1 The status of samples is defined by the reference method used and should be notified as: N: Negative, P: Positive, TN: True Negative, TP: True Positive, FN: False Negative, FP: False Positive SN Sample Number Comparative technique Coris Test Results Positive Positive TP Positive Low Positive TP Positive Low Positive TP Positive Low Positive TP Positive Low Positive TP Positive Negative FN Positive Negative FN Positive Negative FN Positive Negative FN Positive Negative FN Positive Negative FN Positive Negative FN Positive Negative FN Positive Negative FN Positive Negative FN Positive Negative FN Positive Positive TP Positive Positive TP Positive Positive TP Positive Positive TP Positive Positive TP Positive Positive TP Positive Positive TP Positive Positive TP Positive Positive TP Positive Positive TP Positive Positive TP Positive Positive TP Positive Positive TP Positive Positive TP Positive Positive TP Positive Positive TP Positive Positive TP Positive Positive TP Positive Positive TP Positive Positive TP Positive Positive TP Positive Positive TP A6 Positive Positive TP A5 Positive Positive TP A2 Positive Positive TP Positive Positive TP

8 SN Sample Number Comparative technique Coris Test Results Positive Positive TP Positive Positive TP Positive Positive TP Positive Positive TP Positive Positive TP Positive Positive TP Positive Positive TP Positive Positive TP Positive Positive TP Positive Positive TP Positive Positive TP Positive Positive TP Positive Positive TP Positive Positive TP Positive Positive TP

9 Table 2. Results for Each Specimen from patients Group 2 SN Sample Number Comparative technique Coris Test Results 58 8 Negative Negative TN Negative Negative TN Negative Negative TN 61 9 Negative Negative TN Negative Negative TN Negative Negative TN Negative Negative TN A3 Negative Negative TN Negative Negative TN Negative Negative TN Negative Negative TN Negative Negative TN Negative Negative TN Negative Negative TN Negative Negative TN Negative Negative TN Negative Negative TN Negative Negative TN Negative Negative TN Negative Negative TN Negative Negative TN Negative Negative TN Negative Negative TN Negative Negative TN Negative Negative TN Negative Negative TN Negative Negative TN Negative Negative TN Negative Negative TN Negative Negative TN Negative Negative TN Negative Negative TN Negative Negative TN Negative Negative TN Negative Negative TN Negative Negative TN Negative Negative TN Negative Negative TN Negative Negative TN Negative Negative TN Negative Negative TN Negative Negative TN Negative Negative TN

10 Table 2. Discordant Results for Each Specimen from patients Group 1 SN Sample Number Comparative technique Coris Test Results Coris Test CU EIA Bartels Positive Negative FN Positive Positive Positive Negative FN Positive Positive Positive Negative FN Low Positive Positive Positive Negative FN Low Positive Positive - Additional results: ICT Binax & CU Positive Negative FN Negative Negative Negative Positive Negative FN Negative Negative Negative Positive Negative FN Positive Positive Positive Negative FN Positive Negative Negative () Positive Negative FN Positive Positive Negative () Positive Negative FN Low Positive N.A. Negative () Positive Negative FN Positive Positive -